Retrograde signals from the chloroplast control expression of nuclear genes. A large fraction of these genes is affected rapidly upon light intensity shifts. This study was designed to address the interdependence of signaling pathways involved in the rapid high light response and redox and reactive oxygen species signaling by exploiting the glutathione and ascorbate deficient mutants pad2 and vtc1. In the first set of experiments the transcriptional response of the two transcription factors ERF6 and ERF105 that had previously been shown to rapidly respond to light was shown to be deregulated in the pad2 mutant but not in the vtc1 background...

Defective Kernel1 (DEK1) is a plant-specific calpain involved in epidermis specification and maintenance. DEK1 regulation of the epidermal cell wall is proposed to be key to ensure tissue integrity and coordinated growth. Changes in the expression of DEK1 are correlated with changes in the expression of cell wall-related genes. For example, we have found that Lipid transfer protein 3 (LTP3), EXPANSIN 11 (EXP11), and an AP2 transcription factor (AP2TF) are misexpressed in plants with constitutively altered levels of DEK1 activity...

The molecular basis behind shade tolerance in plants is not fully understood. Previously, we have shown that a connection may exist between shade tolerance and dwarfism, however, the mechanism connecting these phenotypes is not well understood. In order to clarify this connection, we analyzed the transcriptome of a previously identified shade-tolerant mutant of perennial ryegrass (Lolium perenne L.) called shadow-1. shadow-1 mutant plants are dwarf, and are significantly tolerant to shade in a number of environments compared to wild-type controls...

The recombinant isoforms Lc-LTP1 and Lc-LTP3 of the lentil lipid transfer protein were overexpressed in E. coli cells. It was confirmed that both proteins are stabilized by four disulfide bonds and characterized by a high proportion of the α-helical structure. It was found that Lc-LTP1 and Lc-LTP3 possess antimicrobial activity and can bind fatty acids. Both isoforms have the ability to bind specific IgE from sera of patients with food allergies, which recognize similar epitopes of the major peach allergen Pru p 3...

Plant Lipid-Transfer Proteins (LTPs) exhibit the ability to reversibly bind/transport lipids in vitro. LTPs have been involved in diverse physiological processes but conclusive evidence on their role has only been presented for a few members, none of them related to seed physiology. Arabidopsis seeds rely on storage oil breakdown to supply carbon skeletons and energy for seedling growth. Here, Arabidopsis ltp3 mutant was analyzed for its ability to germinate and for seedling establishment. Ltp3 showed delayed germination and reduced germination frequency...

Plant lipid transfer proteins (LTPs) are encoded by multigene families and play important roles in plant physiology. One full-length cDNA encoding an Arabidopsis LTP3 homologue was isolated from maize by RT-PCR and named as ZmLTP3. RT-PCR analysis indicated that the ZmLTP3 expression is induced by salicylic acid (SA), mannitol and salt. Furthermore, in different tissues the ZmLTP3 displayed different expression patterns, indicating that ZmLTP3 may play multiple roles in stress resistance. Over-expression of ZmLTP3 in wild-type Arabidopsis resulted in the increased salt tolerance...

Long-term potentiation (LTP) in the hippocampus is a fundamental process underlying learning and memory in the brain. At CA3-CA1 synapses, three discrete forms of LTP (LTP1, 2, and 3) have been differentiated on the basis of their persistence, maintenance mechanisms, Ca(2+) signaling pathways, expression loci, and electrophysiological requirements. We previously showed that LTP2 and LTP3 involve a presynaptic expression component that is established in a translation-dependent manner. Here we investigate the locus of translation required for presynaptic expression...

Several lipid-transfer proteins were reported to modulate the plant response to biotic stress; however, whether lipid-transfer proteins are also involved in abiotic stress remains unknown. This study characterized the function of a lipid-transfer protein, LTP3, during freezing and drought stress. LTP3 was expressed ubiquitously and the LTP3 protein was localized to the cytoplasm. A biochemical study showed that LTP3 was able to bind to lipids. Overexpression of LTP3 resulted in constitutively enhanced freezing tolerance without affecting the expression of CBFs and their target COR genes...

The phenomenon of pistil abortion widely occurs in Japanese apricot, and imperfect flowers with pistil abortion seriously decrease the yield in production. Although transcriptome analyses have been extensively studied in the past, a systematic study of differential gene expression has not been performed in Japanese apricot. To investigate genes related to the pistil development of Japanese apricot, high-throughput sequencing technology (Illumina) was employed to survey gene expression profiles from perfect and imperfect Japanese apricot flower buds...

A previously identified sterol catabolic gene cluster is widely dispersed among actinobacteria, enabling them to degrade and grow on naturally occurring sterols. We investigated the physiological roles of various genes by targeted inactivation in mutant RG32 of Rhodococcus rhodochrous, which selectively degrades sterol side-chains. The ltp3 and ltp4 deletion mutants were each completely blocked in side-chain degradation of β-sitosterol and campesterol, but not of cholesterol. These results indicated a role for ltp3 and ltp4 in the removal of C24 branches specifically...

Long-term potentiation (LTP) is an important process underlying learning and memory in the brain. At CA3-CA1 synapses in the hippocampus, three discrete forms of LTP (LTP1, 2, and 3) can be differentiated on the basis of maintenance and induction mechanisms. However, the relative roles of pre- and post-synaptic expression mechanisms in LTP1, 2, and 3 are unknown. Neurotransmitter release in the expression of LTP1, 2, and 3 was measured via FM 1-43 destaining from CA3 terminals in hippocampal slices from male Wistar rats (7-8 wk)...

Lily stigma/style cysteine-rich adhesin (SCA), a plant lipid transfer protein (LTP) which is secreted into the extracellular matrix, functions in pollen tube guidance in fertilization. A gain-of-function mutant (ltp5-1) for Arabidopsis LTP5, an SCA-like molecule, was recently shown to display defects in sexual reproduction. In the current study, it is reported that ltp5-1 plants have dwarfed primary shoots, delayed hypocotyl elongation, various abnormal tissue fusions, and display multibranching. These mutant phenotypes in vegetative growth are recessive...

Long-term potentiation (LTP) of synaptic strength is a long-lasting form of synaptic plasticity that has been linked to information storage. Although the molecular and cellular events underlying LTP are not yet fully understood, it is generally accepted that changes in dendritic spine calcium levels as well as local protein synthesis play a central role. These two processes may be influenced by the presence of a spine apparatus, a distinct neuronal organelle found in a subpopulation of telencephalic spines...

Long-term potentiation (LTP) of synaptic transmission is a primary experimental model of memory formation in neuronal circuits. Because of the intellectual appeal and scientific fecundity of the field, it is perhaps unsurprising that the literature on LTP contains many complex and often contradictory findings. Recognition that LTP is not a unitary phenomenon and mechanisms can differ between brain regions has resolved some controversy. However, further categorization can be made of mechanistically discrete forms of LTP at the same set of synapses...

In Streptomyces antibioticus, there are two genes TYRA and ORF438 required for the melanin biogenesis. To investigate whether expression of these two genes in cotton can change cotton fiber colour, we modified the TYRA and ORF438 genes to make their codon usage closer to the codon preference of cotton fiber genes. The resulting versions of these two genes were referred to as DTYRA and DORF438, respectively. Vacuolar targeting signals were also added to their ends. Under the cotton fiber specific LTP3 promoter, DORF438 and DTYRA were first transformed into model plant tobacco (Nicotiana tabacum)...

Neurophysiological, biochemical and molecular processes described in the integration of memory are closely related with neurotransmitters such as glutamate and serotonin (SHT) and with the function of calcium and potassium ion channels more than with cholinergic activity. Infact, glutamate and 5-HT receptors are closely related with Long-Term potentiation (L TP) processes, the mechanism by which memory is preserved throughout time. That is, the activation of the 5-HTI receptor triggers a transduction signal that after influencing nuclear cell activity, provokes several presynaptic changes, which leads to the displacement of magnesium from the postsynaptic area depolarizing the neuron and leading to the activation of N-methyl-D-aspartate receptors (NMDA)...

A cotton Ltp3 gene and its 5' and 3' flanking regions have been cloned with a PCR-based genomic DNA walking method. The amplified 2.6 kb DNA fragment contains sequences corresponding to GH3 cDNA which has been shown to encode a lipid transfer protein (LTP3). The gene has an intron of 80 bp which is located in the region corresponding to the C-terminus of LTP3. The Ltp3 promoter was systematically analyzed in transgenic tobacco plants by employing the Escherichia coli beta-glucuronidase gene (GUS) as a reporter...

Lipid transfer proteins (LTPs) are small, basic and abundant proteins in higher plants. They are capable of binding fatty acids and of transferring phospholipids between membranes in vitro. LTPs from this family contain a signal peptide and are secreted in the cell wall. Their biological function is presently unknown. LTPs have been suggested to participate to cutin assembly and to the defense of the plants against pathogens. A genetic approach should prove useful to provide clues on their in vivo functions...

We have characterized three cDNAs from a gene family encoding lipid transfer proteins, LTP, from Arabidopsis thaliana (Wassilewskija). In addition to the already characterized Ltp1, our analysis includes Ltp2 and Ltp3, two sequences previously known as expressed sequence tags (EST) only. The deduced amino acid sequences of the three cDNAs share 56 to 57% identity and show unique tissue- and cell-specific expression. Genes Ltp1 and LTp2 are located within approximately 1.4 kb of each other in tandem orientation...